Sheldon is most likely just lightening up. Sometimes it's better to sell over time within an environment of general optimism as opposed to attempting to sell on a one or two day run-up following positive news, sometimes that can be hectic. I don't believe the Anonymous name reappearing is much to be concerned with. Sheldon, for the moment, like many market investors is aware of other stocks that are outperforming and the ones that aren't.
Investors jump around all the time from one security to the next, all because of the impatience that I'm holding a dud while this other one is on the move and I'm being left behind. Like Jesse Livermore once commented, the game is about patience. Isn't that right, Dave?